I was working to get things working for the evening of Sat 19th (NZ time) but noticed an issue during the afternoon that stopped much in the way of new feature development.

Once I had the the display working okay I added a couple of features:

One permanent message (hardcoded into the sketch) to display.

Four “slots” used to store the last four SMS messages received. When a new message is received the oldest message is overwritten. (The display order doesn’t change however–i.e. the message in slot 1 is always displayed after the permanent message, even if it’s not the most recent/oldest.)